Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

Name:	us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Subsequent Events (Details) (USD $) In Millions, unless otherwise specified	Oct. 28, 2012	Oct. 26, 2012	Oct. 30, 2012 Revolving Credit Facility [Member]	Sep. 30, 2012 Revolving Credit Facility [Member]	Jul. 30, 2012 Revolving Credit Facility [Member]	Apr. 11, 2012 Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Credit Agreement, current borrowing capacity			$ 730.0	$ 730.0	$ 655.0	$ 630.0
Approximate cash payment for oil and gas properties in Akr-La- Tex region	$ 215	$ 215